Pelvicoabdominal plexiform neurofibroma is a rare and complicated form of type 1 neurofibromatosis (NF1), distinguished by developing benign nerve sheath tumors in the pelvis and abdomen. A male patient, aged 26, came to our center with dysuria, abdominal bloating, rectal mucosa prolapses, and trouble walking and moving legs. Physical examination revealed a palpable mass of solid consistency fixed in the pelvic cavity to the abdominal cavity. A large and extensive mass in the pelvic to the abdominal region can be evaluated with multimodality radiological imaging, including ultrasound, computed tomography, and magnetic resonance imaging. Imaging is crucial for diagnosis, evaluation of extension, and early detection of potential malignant transformation in these patients. The patient was scheduled for palliative surgical resection due to the extensive mass; however, he did not survive while waiting for the operation. Pathology examination and immunohistochemical staining revealed positive S-100 protein, indicating the neural crest originate lesion. We report the clinical and radiological features of plexiform neurofibroma in a young male patient, confirmed by pathology examination.